Caring for and improving the lives of mothers and families, Duke Maternal-Fetal Medicine (MFM) is an academically oriented group with the requirements to participate in the Maternal-Fetal Medicine Units Network (MFMU). We are well-suited to be an MFMU site given our research infrastructure, successful track record in basic and translational research, and patient volume. With 4 primary research faculty and 10 research staff, Duke MFM has a highly functional research team with over 10 years of experience in single and multi-center studies. Content expertise includes prematurity, premature rupture of membranes, fetal growth restriction, racial disparities, maternal immunization, and maternal medical conditions - particularly thrombosis and hemostasis. Technical expertise includes study design, recruitment and retention, molecular biology, data safety monitoring, coordinating and analysis, and decision/cost-effectiveness modeling. With 14 faculty, 6 fellows, 9 midwives, and 8 nurse clinicians, Duke MFM provides full service high-risk prenatal care and delivery, prenatal diagnosis, and consultative services for the Duke University Health System (DUHS). For the MFMU, we propose to recruit participants from -5,500 annual births across two DUHS institutions in Durham, North Carolina - Duke University Medical Center (-3,300) and Durham Regional Hospital (DRH) (-2,200). High risk conditions like hypertension, diabetes, asthma, multi-fetal gestation, prematurity, and low birthweight occur among half of all births across DUHS. Duke MFM has a productive relationship with Neonatology, providing continued expertise and support for their participation in the Neonatal Research Network. Further, we have active partnerships across the Duke University campus including pediatrics, anesthesia, infectious diseases, cardiology, hematology, pathology, genetics, pharmacology, epidemiology, research pharmacies and the Duke Translational Medicine Institute (NIH Clinical & Translational Science Award), which can aid our success in the MFMU. Duke MFM is committed to work cooperatively with NICHD and the MFMU and has the expertise, resources, and institutional support to be a productive and successful site involved in multicenter collaborative research involving perinatal health.